Abstract:
Driven by factors such as the increasingly mobile use of the web and the proliferation of geo-positioning technologies, the web is rapidly acquiring a spatial aspect. Specifically, content and users are being geo-tagged, and services increasingly exploit these tags. The research community is hard at work inventing means of efficiently supporting new spatial querying functionality.

Points of interest with a web presence, called spatial web objects, have a location as well as a textual description. Spatio-textual queries return such objects that are near a location argument and are relevant to a text argument. An important element in enabling such queries is to be able to rank spatial web objects. Another is to be able to determine the relevance of an object to a query. Yet another is to enable the efficient processing of such queries. The talk covers recent results on spatial web object ranking and spatio-textual querying obtained by the speaker and his colleagues.

About the speaker:
Christian S. Jensen is a Professor of Computer Science at Aarhus University, Denmark. His research concerns data management and spans semantics, modeling, and indexing and query processing. Since the mid-90s, his focus has been on spatio-temporal data management. He is an IEEE Fellow and a member of the Royal Danish Academy of Sciences and Letters, the Danish Academy of Technical Sciences, and the EDBT Endowment. He is vice chair of ACM SIGMOD and a trustee emeritus of the VLDB Endowment. He received the Ib Henriksen Research Award 2001
for his research in mainly temporal data management, Telenor's Nordic Research Award 2002 for his research in mobile services, and the Villum Kann Rasmussen Award for Technical and Scientific Research 2011 for his general research contributions.

He is an editor-in-chief of The VLDB Journal and has served on the editorial boards of ACM TODS, IEEE TKDE, and the IEEE Data Engineering Bulletin. He was PC chair or co-chair for SSTD 2001, EDBT 2002, VLDB 2005, MobiDE 2006, MDM 2007, DMSN 2008, TIME 2008, and ACM SIGSPATIAL GIS 2011. He will be PC co-chair for APWeb 2012 and IEEE ICDE 2013.